This section contains information to consider before starting to configure SAP and contains examples of typical SAP configurations. It also includes a step-by-step process for configuring and protecting SAP with LifeKeeper.
Also, refer to your SPS for Linux Technical Documentation for instructions on configuring your SPS Core resources (for example, file system resources).
There are many possible configurations of database and application servers in an SAP Highly Available (HA) environment. The specific steps involved in setting up SAP for LifeKeeper protection are different for each configuration, so it is important to recognize the configuration that most closely fits your requirements. Some supported configuration examples are:
The configurations pictured in the above examples consist of two servers hosting the Central Services Instance(s) with an ERS Instance, Database Instance, Primary Application Server Instance and zero or more additional redundant Application Server Instances (AS). Although it is possible to configure SAP with no redundant Application Servers, this would require users to log in to the ASCS Instance or SCS Instance which is not recommended by SAP. The ASCS Instance, SCS Instance and Database servers have access to shared file storage for database and application files.
While Central Services do not use a lot of resources and can be switched over very fast, Databases have a significant impact on switchover speeds. For this reason, it is recommended that the Database Instances and Central Services Instances (ASCS and SCS) be protected through two distinct LifeKeeper hierarchies. They can be run on separate servers or on the same server.
The following are technical notes related to configuring SAP to run in an HA environment. Please see subsequent topics for step-by-step instructions on protecting SAP with LifeKeeper.